<template>
	<div class="type-nav">
		<!-- <h1>{{categoryList}}</h1> -->
		<div class="container" @mouseleave="change2Show" >
			<h2 class="all" @mouseenter="change1Show" >全部商品分类</h2>
			<nav class="nav">
				<a href="###">服装城</a>
				<a href="###">美妆馆</a>
				<a href="###">尚品汇超市</a>
				<a href="###">全球购</a>
				<a href="###">闪购</a>
				<a href="###">团购</a>
				<a href="###">有趣</a>
				<a href="###">秒杀</a>
			</nav>
			<div class="sort" v-show="show" >
				<div class="all-sort-list2" @click="goSearch">
					<!-- @mouseleave="changeIndex(2,index)" 鼠标移出时，取消样式 -->
					<div @mouseleave="changeIndex(2,index)" class="item" :class="{cur:categoryListIndex==index}" v-for="(c1,index) in categoryList.slice(0,15)"
					 :key='c1.categoryId'>
						<!-- <div class="item" v-if="index < 15" v-for="(c1,index) in categoryList" :key = 'c1.categoryId' > -->
						<h3 @mouseenter="changeIndex(1,index)">
							<a :data-categoryName='c1.categoryName'  :data-category1Id='c1.categoryId'>{{c1.categoryName}}</a>
						</h3>
						
						<div class="item-list clearfix">
							<div class="subitem" v-for="(c2,index) in c1.categoryChild" :key='c2.categoryId'>
								<dl class="fore">
									<dt>
										<a :data-categoryName='c2.categoryName' :data-category2Id='c2.categoryId' >{{c2.categoryName}}</a>
									</dt>
									<dd>
										<em v-for="(c3,index) in c2.categoryChild" :key='c3.categoryId'>
											<a :data-categoryName='c3.categoryName' :data-category3Id='c3.categoryId'>{{c3.categoryName}}</a>
										</em>
									</dd>
								</dl>
							</div>
						</div>
					</div>
				</div>
			</div>
		</div>
	</div>
</template>

<script>
	import {
		mapState
	} from 'vuex'
	//引入lodash 进行节流
	import throttle from 'lodash/throttle'
	export default {
		name: 'TypeNav',
		//组件挂载完毕，向服务器发送请求
		data() {
			return {
				//存储用户鼠标当前以及分类的索引
				categoryListIndex: -1,
				show:true
			}
		},
		mounted() {
			// //通知Vuex发送请求
			// this.$store.dispatch('cateoryList')
			//当组件挂载完毕，让show为false
			// console.log(this.$route.name)
			if(this.$route.name == 'search'){
				this.show = false
			}
			
		},
		computed: {
			...mapState({
				//右侧需要的是一个函数。当使用计算属性时，右侧函数会立即执行一次
				//注入一个参数state
				categoryList: (state) => state.home.categoryList,
			})
		},
		methods: {
			//鼠标进入后，修改响应式数据categoryListIndex
			// changeIndex(a,index){
			// 	if(a==1){
			// 		this.categoryListIndex = index
			// 	}else{
			// 		this.categoryListIndex = -1
			// 	}
			// 	// console.log(this.categoryListIndex)
			// }
			//节流写法_.throttle(function(){})
			//js动态展示样式
			changeIndex: throttle(function(a, index) {
				//如果是一级分类，把鼠标所在的索引赋值给categoryListIndex
				if (a == 1) {
					this.categoryListIndex = index
				} else {
					this.categoryListIndex = -1
				}
				// console.log(this.categoryListIndex)
			}, 50),
			goSearch(e) {
				//事件委托存在的一些问题
				//1、点击的是不是a标签
				//2、获取参数
				//3、区分一级、二级、三级分类

				//1、把a标签加上自定义属性,然后用target拿到节点判断是否有自定义属性
				// console.log(e.target)
				let element = e.target
				//节点有个属性dataset，可以获取节点的自定义属性与属性值，是个对象，可以解构赋值。
				let {categoryname,category1id,category2id,category3id} = element.dataset
				//如果标签的身上拥有categoryname，那么一定是a标签
				// console.log(categoryname)
				if(categoryname){
					//整理参数
					let loction = {name:'search'}
					let query = {categoryName:categoryname}
					//判断是几级分类
					if(category1id){
						query.category1Id = category1id
					}else if(category2id){
						query.category2Id = category2id
					}else{
						query.category3Id = category3id
					}
					//判断路由中有没有params参数
					if(this.$route.params){
						loction.params = this.$route.params
						loction.query = query
						this.$router.push(loction)
					}
					
				}
			},
			change1Show(){
				if(this.$route.name == 'search'){
					this.show = true
				}
			},
			change2Show(){
				if(this.$route.name == 'search'){
					this.show = false
				}
			}
			
		}
	}
</script>

<style scoped lang="less">
	.type-nav {
		border-bottom: 2px solid #e1251b;

		.container {
			width: 1200px;
			margin: 0 auto;
			display: flex;
			position: relative;

			.all {
				width: 210px;
				height: 45px;
				background-color: #e1251b;
				line-height: 45px;
				text-align: center;
				color: #fff;
				font-size: 14px;
				font-weight: bold;
			}

			.nav {
				a {
					height: 45px;
					margin: 0 22px;
					line-height: 45px;
					font-size: 16px;
					color: #333;
				}
			}

			.sort {
				position: absolute;
				left: 0;
				top: 45px;
				width: 210px;
				height: 461px;
				position: absolute;
				background: #fafafa;
				z-index: 999;

				.all-sort-list2 {
					.item {
						h3 {
							line-height: 30px;
							font-size: 14px;
							font-weight: 400;
							overflow: hidden;
							padding: 0 20px;
							margin: 0;

							a {
								color: #333;
							}
						}

						.item-list {
							display: none;
							position: absolute;
							width: 734px;
							min-height: 460px;
							background: #f7f7f7;
							left: 210px;
							border: 1px solid #ddd;
							top: 0;
							z-index: 9999 !important;

							.subitem {
								float: left;
								width: 650px;
								padding: 0 4px 0 8px;

								dl {
									border-top: 1px solid #eee;
									padding: 6px 0;
									overflow: hidden;
									zoom: 1;

									&.fore {
										border-top: 0;
									}

									dt {
										float: left;
										width: 54px;
										line-height: 22px;
										text-align: right;
										padding: 3px 6px 0 0;
										font-weight: 700;
									}

									dd {
										float: left;
										width: 415px;
										padding: 3px 0 0;
										overflow: hidden;

										em {
											float: left;
											height: 14px;
											line-height: 14px;
											padding: 0 8px;
											margin-top: 5px;
											border-left: 1px solid #ccc;
										}
									}
								}
							}
						}

						&:hover {
							.item-list {
								display: block;
							}
						}
					}

					// .item:hover{
					// 	background-color: skyblue;
					// }
					.cur {
						background-color: skyblue;
					}
				}
			}
		}
	}
</style>
